1. Field of the Invention
This invention relates to comminution and extrusion apparatus and, more particularly, to a novel comminution and extrusion apparatus and method for finely comminuting a frozen block of frozen food item and extruding the resulting food product.
2. The Prior Art
Freezing a suitably pasteurized food product is an excellent method for preserving the flavor of the food product whether it is obtained from fruit sources, vegetable sources, artificially flavored liquids, dairy products, or combinations of the same. However, any hard-frozen food product from these sources will exhibit a hard, crystalline structure that is difficult to break. When broken, the food product exposes sharp, needle-like crystals of ice. The direct consumption of such frozen products is unpleasant and can be injurious to sensitive mouth tissue.
Numerous attempts are made to provide frozen fruits as whole items (such as berries, cherries and the like) or as large pieces (such as cantaloupes, peaches, and the like). When eaten, these products must be presented in the partially thawed state in an attempt to overcome the problem of hard, difficult to eat items coupled with the corresponding problem of ice crystal formation. Regrettably, freezing also destroys much of the cellular structure of the particular fruit item so that in its partially thawed state the fruit is mushy and lacks a desirable degree of mouth feel. Ice crystals also cause segregation of the water in the frozen item resulting in uneven flavor distribution.
Items such as ice cream eaten in their frozen state require that great care is taken to assure that ice crystal formation is held to a minimum in order to provide the consumer with a product having an appropriate "mouth feel," that is, a desirable tactile sensation in the mouth when eaten. Historically, an answer to the problem of ice crystal formation has been to heavily lace the particular food product with stabilizers such as corn syrups, carrageenan, guar gum, locust bean gum, and the like. It is also a common practice to whip the food product during freezing in order to entrap large quantities of air bubbles. Extensive use is also made of antioxidants, enzyme inhibitors, and texture enhancers such as soy protein and enzyme modified protein concentrates to improve and even control the whipability, texture and creaminess of the finished product.
Another ice cream-type food product is shipped and stored in the liquid state prior to being frozen into a soft frozen product at the retail location. This product has a relatively short shelf life. Also, the original, fresh flavor has been diluted or otherwise obscured by the addition of extraneous products such as stabilizers, antioxidants, enzyme inhibitors, texture enhancers, preservative, and the like.
In view of the foregoing it would be an advancement in the art to provide an apparatus and method that produces a frozen food product which is prepared from sources of fresh edible products such as fruits, vegetables, dairy products and the like, which are suitably pasteurized prior to being hard frozen into billets, blocks, or bricks. A further advancement in the art would be that the frozen billets could be shipped and stored in the hard-frozen state with the hard-frozen billet being suitably comminuted with this novel apparatus prior to retail sale and consumption so as to produce a soft-frozen food product. It would be a significant advancement in the art to have the ice crystals mechanically comminuted to produce a smooth-textured product. Advantageously, the hard frozen state of the billet significantly improves the shelf life of the food product and also retains the fresh flavor of the particular product. Such an invention is disclosed and claimed herein.